<template>
  <div>
    <!-- 面包屑导航区域 -->
    <el-breadcrumb separator-class="el-icon-arrow-right">
      <el-breadcrumb-item :to="{ path: '/home' }">首页</el-breadcrumb-item>
      <el-breadcrumb-item>商品管理</el-breadcrumb-item>
      <el-breadcrumb-item>添加商品</el-breadcrumb-item>
    </el-breadcrumb>
    <!-- 卡片视图区域 -->
    <el-card>
      <!-- 提示区域 -->
      <el-alert title="添加商品信息"
                type="info"
                center
                show-icon
                :closable="false">
      </el-alert>
      <!-- 步骤条区域 -->
      <el-steps :space="200"
                :active="activeIndex-0"
                finish-status="success"
                align-center>
        <el-step title="基本信息"></el-step>
        <el-step title="商品参数"></el-step>
        <el-step title="商品属性"></el-step>
        <el-step title="商品图片"></el-step>
        <el-step title="商品内容"></el-step>
        <el-step title="完成"></el-step>
      </el-steps>
      <!-- Tab栏区域 -->
      <el-form :model="addForm"
               :rules="addFormRules"
               ref="addFormRef"
               label-width="100px"
               label-position="top">
        <el-tabs v-model="activeIndex"
                 :tab-position="'left'"
                 :before-leave="beforeTabLeave">
          <el-tab-pane label="基本信息"
                       name="'0'">
            <el-form-item label="商品名称"
                          prop="goods_name">
              <el-input v-model="addForm.goods_name"></el-input>
            </el-form-item>
            <el-form-item label="商品价格"
                          prop="goods_price">
              <el-input v-model="addForm.goods_price"
                        type="number"></el-input>
            </el-form-item>
            <el-form-item label="商品重量"
                          prop="goods_weight">
              <el-input v-model="addForm.goods_weight"
                        type="number"></el-input>
            </el-form-item>
            <el-form-item label="商品数量"
                          prop="goods_number">
              <el-input v-model="addForm.goods_number"
                        type="number"></el-input>
            </el-form-item>
            <el-form-item label="商品分类"
                          prop="goods_cat">
              <el-cascader v-model="addForm.goods_cat"
                           :options="catelist"
                           expand-trigger="hover"
                           :props="cateProps"
                           @change="handleChange"></el-cascader>
            </el-form-item>
          </el-tab-pane>
          <el-tab-pane label="商品参数"
                       name="1">
            <!-- 渲染表单的item项 -->
            <el-form-item label=""></el-form-item>
          </el-tab-pane>
          <el-tab-pane label="商品属性"
                       name="2">商品属性</el-tab-pane>
          <el-tab-pane label="商品图片"
                       name="3">商品图片</el-tab-pane>
          <el-tab-pane label="商品内容"
                       name="4">商品内容</el-tab-pane>
        </el-tabs>
      </el-form>
    </el-card>
  </div>
</template>

<script>
export default {
  data () {
    return {
      activeIndex: 0,
      // 添加商品的表单数据对象
      addForm: {
        goods_name: '',
        goods_price: 0,
        goods_weight: 0,
        goods_number: 0,
        // 商品所属的分类数组
        goods_cat: []
      },
      addFormRules: {
        goods_name: [{ required: true, message: '请输入商品名称', trigger: 'blur' }],
        goods_price: [{ required: true, message: '请输入商品价格', trigger: 'blur' }],
        goods_weight: [{ required: true, message: '请输入商品重量', trigger: 'blur' }],
        goods_number: [{ required: true, message: '请输入商品数量', trigger: 'blur' }],
        goods_cat: [{ required: true, message: '请选择商品分类', trigger: 'blur' }]
      },
      // 商品分类列表
      catelist: [],
      cateProps: {
        label: 'cat_name',
        value: 'cat_id',
        children: 'children'
      }
    }
  },
  ctreated () {
    this.getCateList()
  },
  methods: {
    // 获取所有商品分类数据
    async getCateList () {
      const { data: res } = await this.$http.get('categories')
      if (res.meta.status !== 200) {
        return this.$message.error('获取商品分类数据失败!')
      }
      this.catelist = res.data
      console.log(this.catelist)
    },
    // 级联选择器选中项变化，会触发这个函数
    handleChange () {
      console.log(this.addForm.goods_cat)
      if (this.addForm.goods_cat.length !== 3) {
        this.addForm.goods_cat = []
      }
    },
    beforeTabLeave (activeName, oldActiveName) {
      console.log('即将离开的标签页名字是:' + oldActiveName);
      console.log('即将进入的标签页名字是:' + activeName);

    }
  }
}
</script>

<style lang="less" scoped>
.el-form-item {
  margin-left: 0;
}
</style>